Cisco IOS XR 4.1.2 through 5.1.1 on ASR 9000 devices, when a Trident-based line card is used, allows remote attackers to cause a denial of service (NP chip and line card reload) via malformed IPv6 packets, aka Bug ID CSCun71928.
Cisco IOS XR 3.8.1 through 4.2.0 does not properly process fragmented packets within the RP-A, RP-B, PRP, and DRP-B route-processor components, which allows remote attackers to cause a denial of service (transmission outage) via (1) IPv4 or (2) IPv6 traffic, aka Bug ID CSCuh30380.